From owner-freebsd-alpha Mon Nov 6 2: 7:26 2000 Delivered-To: freebsd-alpha@freebsd.org Received: from finch-post-11.mail.demon.net (finch-post-11.mail.demon.net [194.217.242.39]) by hub.freebsd.org (Postfix) with ESMTP id 913F337B4C5; Mon, 6 Nov 2000 02:07:23 -0800 (PST) Received: from nlsys.demon.co.uk ([158.152.125.33] helo=herring.nlsystems.com) by finch-post-11.mail.demon.net with esmtp (Exim 2.12 #1) id 13sjBQ-0001II-0B; Mon, 6 Nov 2000 10:07:22 +0000 Received: from salmon.nlsystems.com (salmon.nlsystems.com [10.0.0.3]) by herring.nlsystems.com (8.9.3/8.8.8) with ESMTP id KAA16412; Mon, 6 Nov 2000 10:14:06 GMT (envelope-from dfr@nlsystems.com) Date: Mon, 6 Nov 2000 10:14:06 +0000 (GMT) From: Doug Rabson To: Peter Jeremy Cc: Mike Smith , alpha@FreeBSD.ORG Subject: Re: cvs commit: src/sys/boot/alpha/common main.c src/sys/boot/al In-Reply-To: <00Nov6.091801est.115213@border.alcanet.com.au> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-alpha@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Mon, 6 Nov 2000, Peter Jeremy wrote: > On Fri, Oct 27, 2000 at 10:28:38AM +0100, Doug Rabson wrote: > >On Thu, 26 Oct 2000, Mike Smith wrote: > >> Forgive the silly question, but is there any reason that boot1 doesn't > >> read the load address from the loader object? > > > >On alpha, /boot/loader is just a binary (the headers have been stripped > >off). When I wrote it, I didn't think I would be able to squeeze an ELF > >loader into the space available. Currently there are 280 bytes spare - > >probably not enough. > > Any reason why you couldn't have a primitive header: eg magic number > and start address in /boot/loader. The code to read this and > appropriately relocate /boot/loader shouldn't be too big. I agree that > it's undesirable to wind up with yet another incompatible object > format, but having an unbootable machine because /boot/loader expects > a different load address to boot1 is even less desirable. That would also involve changing the ABI between boot1 and loader. The problem with that is that loader is updated on installworld but boot1 isn't so its easy to create a mismatch. The load address of loader is essentially fixed. -- Doug Rabson Mail: dfr@nlsystems.com Phone: +44 20 8348 6160 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-alpha" in the body of the message